The seventh biennial Gordon Research Conference on Gravitational Effects on Living Systems will be held July 1-6, 2001 at Connecticut College. The theme of the meeting is mechanosensing, an ancient sensory capability. Approximately 100 participants are expected, including 23-25 speakers and 13 discussion leaders. The participation of trainees will be actively sought. While gravity affects living systems in many ways, mechanosensing is an appropriate focus for the meeting. Gravity is detected by mechanosen-sors, but most importantly for the meeting's success, this is an exciting and critical time for research on mechanosensors. The crystal structure of a prokaryotic mechanosensitive channel has recently been elucidated. Behavioral screens of eukaryotic genetic model animals, the yeast, roundworm and fruitfly, have yielded different mechanosensory cascades, including two putative classes of mechanosensory ion channels. Strong functional parallels have recently been shown between the mechanosensory chordotonal organs of flies and the sensory hair cells of the vertebrate inner ear. Intense genetic scrutiny of the mammalian inner ear has produced several pivotal successes in identifying genetic mutations underlying inner ear pathology in mice and humans. In addition to such work on specialized mechanosensors, there have been major recent advances in understanding the responses of nonmechanosensory tissues (muscle, bone, shoots and roots of plants) to mechanical input. The proposed meeting will bring together scientists who don't normally have a chance to meet either because they study different kinds of organisms (microorganisms, plants or animals), or different kinds of mechanical responses (mechanically evoked cascades in specialized mechanosensors vs. tissues that re- model in response to mechanical inputs, including gravity), or because they take widely different approaches (physiology vs. genetics). Moreover, the Gordon Conference format facilitates informal communications and discussions of controversial issues. These factors will promote inter-disciplinary transfer of ideas and approaches and the generation of new strategies for the study of mechanotransduction.